Conventionally, as polarizers which can overcome the disadvantage of polarizing plates that about half of incident light is absorbed to result in absorption loss, thereby improving the luminance of liquid crystal displays, elements comprising laminated products of cholesteric liquid crystal layers and 1/4 wavelength plates have been known. In these elements, circularly polarized light transmitted through the cholesteric liquid crystal layers is converted to linearly polarized light by the 1/4 wavelength plates, and the linearly polarized light is allowed to be incident on the polarizing plates in agreement with polarization axes, thereby preventing absorption loss.
However, there is the problem that the luminance of the liquid crystal displays is not so much improved as expected, resulting in uneven display, probably because the linearly polarized light contains large amounts of light components absorbed by the polarizing plates. Further, when prism array layers are arranged for improving the luminance and the efficiency for light utilization by optical path control, there is also the problem that the luminance is largely reduced in a front direction (vertical direction).